The present invention relates to laundry detergent compositions containing a combination of anionic, specified nonionic and cationic surfactants giving improved oily soil detergency.
Heavy duty laundry detergent compositions have for many years contained anionic sulphonate or sulphate surfactant, for example, linear alkylbenzene sulphonate (LAS), together with ethoxylated nonionic surfactants. Examples abound in the published literature.
The preferred ethoxylated alcohol nonionic surfactants giving an optimum balance of properties have generally been those having an alkyl chain length of C12-C15 and an average degree of ethoxylation of 1 to 10, preferably 3 to 7, more preferably about 5.
Longer-chain alcohols having a higher degree of ethoxylation, for example, tallow alcohol (C18) 11EO, have also been used.
These relatively hydrophobic materials of low HLB value are generally liquids at ambient temperature and exhibit excellent oily soil removal.
Longer-chain alcohols having higher degrees of ethoxylation, for example, tallow (C18) alcohol 25EO and 50EO, are solids at ambient temperature and are used as slowly dissolving coating materials, for example, for enzyme or antifoam granules.
Laundry detergent compositions containing cationic (quaternary ammonium) surfactants in combination with anionic and nonionic surfactants are widely disclosed in the patent literature.
It has now surprisingly been found that the combination of anionic and cationic surfactants together with ethoxylated alcohols combining a shorter alkyl chain length and a higher degree of ethoxylation can give enhanced oily soil removal.
WO 94 16052A (Unilever) discloses high bulk density laundry powders based on LAS and conventional nonionic surfactants, and containing small amounts of very highly ethoxylated alcohols, eg tallow alcohol 80EO, as a dissolution aid.
WO 93 02176A (Henkel) discloses the use of highly ethoxylated aliphatic alcohols as xe2x80x9cstructure breakersxe2x80x9d in high bulk density powders containing conventional nonionic surfactants.
EP 293 139A (Procter and Gamble) discloses twin-compartment sachets containing detergent powders. Some powders contain very small amounts of tallow alcohol 25EO.
U.S. Pat. No. 4,294,711 (Procter and Gamble) discloses a textile softening heavy duty detergent composition containing 1 wt % of tallow alcohol 80EO.
WO 92 18594A (Procter and Gamble) discloses builder granules of layered silicate coated with tallow alcohol 50EO.
EP 142 910A and EP 495 345A (Procter and Gamble) disclose antifoam granules containing highly ethoxylated alcohols.
WO 93 19148A (Procter and Gamble) discloses liquid hard surface cleaning compositions containing highly ethoxylated nonionic surfactants optionally plus anionic surfactant.
WO 97 43364, Wo 97 43365A, WO 97 43371A, WO 97 43387A, WO 97 43389A, WO 97 43390A, WO 97 43391A and WO 97 43393A, (Procter and Gamble) disclose laundry detergent compositions containing so-called xe2x80x9cAQAxe2x80x9d alkoxylated quaternary ammonium surfactants in combination with other surfactants.
The present invention provides a built laundry detergent composition comprising
(i) from 5 to 40 wt %, preferably from 7 to 30 wt %, of surfactant consisting essentially of:
(i)(a) an anionic sulphonate or sulphate surfactant,
(i)(b) an ethoxylated alcohol nonionic surfactant of the general formula I
Rxe2x80x94(xe2x80x94Oxe2x80x94CH2xe2x80x94CH2)nxe2x80x94OHxe2x80x83xe2x80x83(I)
wherein R is a hydrocarbyl chain having from 8 to 16 carbon atoms, and the average degree of ethoxylation n is from 20 to 50,
(i)(c) a quaternary ammonium cationic surfactant,
(ii) from 10 to 80 wt % of detergency builder,
(iii) optionally other detergent ingredients to 100 wt %.
The invention also provides a process for laundering textile fabrics by machine or hand, which includes the step of immersing the fabrics in a wash liquor comprising water in which a laundry detergent composition as defined in the previous paragraph is dissolved or dispersed.
The invention further provides the use of a surfactant (i) consisting essentially of
(i)(a) an anionic sulphonate or sulphate surfactant,
(i)(b) an ethoxylated alcohol nonionic surfactant of the general formula I
Rxe2x80x94(xe2x80x94Oxe2x80x94CH2xe2x80x94CH2)nxe2x80x94OHxe2x80x83xe2x80x83(I)
wherein R is a hydrocarbyl chain having from 8 to 16 carbon atoms, and the average degree of ethoxylation n is from 20 to 50,
(i)(c) a quaternary ammonium cationic surfactant,
in a laundry detergent composition in an amount of from 5 to 40 wt %, to improve the oily soil detergency of the composition.